I have never done this type of modification, but I have owned /5's, /6's and/7's. First thing you would need are /5 or 1974, /6 handle bar control collars. These have the bosses to hold those switches. It has been a long time since I had to fiddle with the switches on my /5, but you would want to compare wiring diagrams to try to parse out which wires affect which function. It should be do-able. Switching is switching, right/left turn signals, electric start, high/low beam, flash-to-pass, horn. There is also the front brake light switch to consider. /5 wire bundles have tinned ends but the 1974 switches should have female spade connectors. This is because the /6 has a circuit board in the headlight, but the /5 main switch is hand wired point to point. There is no OEM Kill switch on the handlebars before 1975 models, so you would have to get creative to retain that function.